NZXT Guardian 921 RB No Power Supply ATX Mid Tower Case. Spacious Interior and Solid Construction: Built from solid .88mm and 1.00mm steel, the Guardian 921 gives the user ample space for large, high-end video cards and space for up to four internal hard drives Updated Design: The all new Guardian 921 RB features a bottom mounted PSU, CPU heatsink cutout, and an extra slot for a 140mm fan at the top for more cooling performance. The all new Guardian 921 RB comes in both red/blue LED combinations Multimedia and peripheral inputs: E-SATA, Intel HD audio, mic, and two USB inputs are standards with the Guardian 921 allowing for maximum peripheral input Constant Temperature Monitoring: Three temperature probe monitoring system allows the user to constantly gauge thermals within the system at all times to prevent overheating Silent Cooling: Comes standard with 3 120mm fans installed to maximize cooling performance with minimal noise Constant Temperature Monitoring: Three temperature probe monitoring system allows the user to constantly gauge thermals within the system at all times to prevent overheating Multimedia and peripheral inputs: E-SATA, Intel HD audio, mic, and two USB inputs are standards with the Guardian 921 allowing for maximum peripheral input Silent Cooling: Comes standard with 3 120mm fans installed to maximize cooling performance with minimal noise Updated Design: The all new Guardian 921 RB features a bottom mounted PSU, CPU heatsink cutout, and an extra slot for a 140mm fan at the top for more cooling performance. The all new Guardian 921 RB comes in both red/blue LED combinations Spacious Interior and Solid Construction: Built from solid .88mm and 1.00mm steel, the Guardian 921 gives the user ample space for large, high-end video cards and space for up to four internal hard drives